UKH

Hi,

I came across a bit of a unique problem. After a lot of searching on the internet and asking a few friends I could not find an answer.

I am used to topping out of trad routes, walking off or abseiling. I am doing a bit of trad climbing around Europe and I have come across a few single pitch trad routes that have bolted anchors at the top as there is no walk off. Most of the routes you can climb with a single rope, clean and lower off like a sport route).

A few of the routes require double ropes to protect them. When using two ropes is it better to have both ropes passing through the ring or just pass a single half rope through when lowering off?

I can see pros and cons for both but I would be grateful if anyone has come across some specific guidance.

It is quicker to just rethread one rope, but the belayer then needs to keep control of lowering you on a single strand (which they should be comfortable doing anyway as you may need to be lowered several metres before the second strand comes into play if you were bailing part way up).

Personally I would just abseil if using doubles and finding a bolted anchor, it's easy to set up, faster than rethreading both strands and will cause less wear on the anchors.

Iff  (by which I mean "if and only if")  1 rope is enough to get to the ground safely then only use 1 rope for the abseil

Because that means no knot is needed to join the two ropes (EDK or whatever)  - simpler, less to get wrong, less to snag etc, Simple = Good.

Never put two ropes through a single ring, maillon or biner to lower off. If one rope crosses the other it can saw through it, I've seen this happen. 

Also worth noting that the ropes will move at different rates if they have different lengths out, if you unclip a piece significantly to one side of the route you will get some movement of the ropes against each other which can damage the sheath so even if the ropes are neatly arranged so neither can put weight on the other they can still cause damage. It is less hazardous than cutting through one strand but will make the rope handle less well.

I'd ab or lower off one strand. Two ropes in one belay can chew each other up.

jk

Leader lowers off on (his/her) quickdrawers, ideally opposing gates as with a single rope to reduce wear on fixed gear, but makes sure ropes run independently. 

Second rethreads to lower or abseil as appropriate. Could thread and use ropes as twins if equally loaded.

Differential movement of ropes could be most serious if a runner rips during lowering, especially if ropes zig zag.

One moving rope can saw through a static rope, but if they are both moving at the same speed in the same direction there is no danger of this.

The problem you're posing is basically the same as you having to lower off gear mid-route on any route: it's just that your anchor is two solid bolts rather than hand-placed gear, e.g. a bomber #1 C4 or, say, a skyhook in a rattly flake.

Assess how far it is to the ground. You may have to ab, you may be ok to lower off. Perhaps try to spend a bit of time thinking more generally about various scenarios where you may need to "get down", because it's best that these don't continue to be surprises: a pair of bolts isn't as much of a problem as trying to get down from a multipitch climb with a broken arm and a novice in tow.

Yes but why take the risk!!! A single half rope is perfectly safe unless there's sharp edges etc.

As stated above I have seen one rope damage the other, expensive and completely unnecessary. 

I deal with this quite a lot on the orme in north Wales, lots of good trad but can't top out so have to lower off. I usually rethread each rope through the independent ring. I.e left rope goes through the left ring, right rope goes through the right ring. this way their not rubbing over each other. if its a equalised lower off i.e only one ring in the middle to lower off then may just be best to abseil off yourself to save ropes rubbing on each other. hope that makes some kind of sense. most probably not though

Thank you to you and everyone. That is perfect. Thanks again for the help.

Apologies if this is obvious but, whatever you end up doing, be completely sure your belayer knows what your are going to do when you get to the top of the route. If you think you're lowering but they think you're abseiling...

If you are doing a double rope abseil, probably best your belayer just keeps you on a slack belay. They won't need to feed out slack as you come down like with a single rope. Avoids any possibility of a screw up.

But can be harder to control on a lower if using a non-assisted tube device, might be a bit less safe in some hands!

Do you mean that you've seen one rope damage the other in this specific scenario; i.e. a statically-weighted, moderate speed lower off? Or are you talking more generally, including dynamic falls with differential slippage?

The former, the topic of the thread.

Hmmm. Not doubting the truth of your anecdote, but to be honest it is a bit difficult to imagine how such a lower could result in significant rope damage, if performed more or less "normally". One would think that any differential rope slip would be very small, and relatively slow. It would be interesting to know what happened, more exactly. Perhaps it was in the nature of a one-off, caused by some unusual (and maybe unknown) variable?

How you're planning to get your gear back is important here - strip on ab or leave anchor set as bottom rope for second?

I completely doubt the truth of their anecdote. I think they're talking about ropes that are not moving together, e.g. an indoor lower-off where a loaded lead rope has been installed on top of an in-situ top rope. Otherwise, twin ropes (not half ropes, but twin ropes) would not exist as a thing...